Effective bridging strategies prior to infusion with tisagenlecleucel results in high response rates and long-term remission in relapsed / refractory large B-cell lymphoma: findings from a German monocentric study. 

Abstract

Incorporating chimeric antigen receptor (CAR)-T cell therapy into relapsed or refractory large B-cell lymphoma (rr LBCL) treatment algorithms has yielded remarkable response rates and durable remissions, yet a substantial portion of patients experience progression or relapse. Variations in outcomes across treatment centers may be attributed to different bridging strategies and remission statuses preceding CAR-T cell therapy. This single center analysis of tisagenlecleucel (tisa-cel) outcomes in the real world reveals response rates surpassing pivotal trials and other real-world reports. Analyzing 29 rr LBCL patients, the median age was 63, with a median of 3 prior treatments. Twenty patients (69%) were refractory to any systemic therapy before CAR-T cell treatment. Following leukapheresis, 25 patients (86%) received bridging therapy with the majority undergoing chemotherapy (52%) or combined modality therapy (32%). Radiotherapy (RT) was part of the bridging strategy in 44%, with moderately hypofractionated involved site RT (30.0 Gy/2.5 Gy) being applied most frequently (64%). Post-CAR-T infusion, the objective response rate at 30 days was 83%, with 55% achieving complete response. Twelve-month progression-free (PFS) and overall survival (OS) were 60% and 74%, respectively, with a median follow up of 11.1 months for PFS and 17.9 months for OS. Factors significantly associated with PFS were chemotherapy sensitivity pre-leukapheresis and response to bridging. The study underscores the importance of minimal tumor burden at CAR-T initiation, emphasizing the need for suitable bridging regimens. The findings advocate for clinical trials and further real-world analyses to optimize CAR-T cell therapy outcomes by identifying the most effective bridging strategies.